What is a Ring Topology? Advantages – Disadvantages.
In a ring topology, the underlying network that connects the computers presents a logical ring-like communication path. At any point in a ring, there are two possible paths to move, one left and one right. The same applies to connected devices in a ring topology; they can communicate from either side to reach another device.
This tutorial will teach us how to set up a ring topology network. What are the advantages and disadvantages?
What are the types of Ring topology types?
There can be two types of ring topologies.
- Unidirectional
- Bi-directional
Although there is a physical connection in both directions in both types. A unidirectional ring can transmit data only in one direction, while a bidirectional ring can transmit data in both directions.
How to set up a Ring topology network?
Ring topologies have two sides for communication. A computer can only have one IP address in a LAN over an Ethernet card. However, there is a need for two outgoing physical links. To accomplish this, the LAN cable from a computer plugs into a network switch or hub. Two cables will be provided in each direction to connect the neighbor HUB/Switch to the form switch/hub.
How will each LAN computer get the IP address? So there must be a router with DHCP. In Ring Topology, any switch/hub can connect to the router. The router works as a gateway between the LAN and the external network. The external network could be the Internet or any other network. When a computer in network topology comes up, it sends a DHCP request to the router for IP address allocation.
What is used in a ring topology for medium access?
The medium access control method in a ring topology is token passing. A token or special packet keeps traversing the ring path. A token is nothing but just an empty frame. Whenever a computer needs to send the data, it tries to hold the token.
If the token is captured, then only the station sends the data else to wait for the token. This allows only one computer to do the transmission at a time. This enables no collision in the ring network.
What are the advantages of Ring Topology advantages?
- Link failure in one direction will not break the communication. For example, if the left network path fails, the transmission will be from the right path.
- Very easy to set up as we need a device with three-port only. This could be a low-cost hub.
- Reduces the chances of collision because of the token passing. This brings better performance than a bus topology.
- Each computer can reach another computer without traversing to a central server.
- Each terminal has equal access.
What are the disadvantages of Ring Topology?
- The data transfer rate is slower as compared to the star topology. A packet will pass all the intermediate nodes before reaching the destination. While in a star topology, a packet needs only to pass a single central hop (e.g., Switch).
- Single point of failure – If any intermediate switches go down between communicating parties, all communication will be lost.
- More expensive as compared to a star topology. As needed, additional hardware other than an ethernet card.